Re: SII SATA request size limit
From: Jens Axboe (axboe_at_suse.de)
Date: 09/15/03
- Previous message: Oleg Drokin: "Re: Another ReiserFS (rpm database) issue (2.6.0-test5)"
- In reply to: Eduardo Casino: "Re: SII SATA request size limit"
- Next in thread: Marcelo Penna Guerra: "Re: SII SATA request size limit"
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Date: Mon, 15 Sep 2003 10:47:22 +0200 To: Eduardo Casino <casino_e@terra.es>
On Fri, Sep 12 2003, Eduardo Casino wrote:
> Hi All,
>
> I had a look at the NetBSD pciide.c driver and found this interesting
> bit of code:
>
> /*
> * Rev. <= 0x01 of the 3112 have a bug that can cause data
> * corruption if DMA transfers cross an 8K boundary. This is
> * apparently hard to tickle, but we'll go ahead and play it
> * safe.
> */
> if (PCI_REVISION(pa->pa_class) <= 0x01) {
> sc->sc_dma_maxsegsz = 8192;
> sc->sc_dma_boundary = 8192;
> }
>
> This is basically the same as setting hwif->rqsize to 15, but the NetBSD
You can do much much better than that, it's pretty simply to just
restrict the segment size and boundary if you have a controller with
such a bug. And then you get the benefit of the larger requests too,
it's basically not a performance hit at that point.
-- Jens Axboe - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
- Previous message: Oleg Drokin: "Re: Another ReiserFS (rpm database) issue (2.6.0-test5)"
- In reply to: Eduardo Casino: "Re: SII SATA request size limit"
- Next in thread: Marcelo Penna Guerra: "Re: SII SATA request size limit"
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Relevant Pages
|
|
